Skateboard type vehicle

ABSTRACT

A light transport vehicle (10) which is directly steerable by a person or persons standing on the vehicle, which vehicle includes (a) an elongated, flexible platform (11); (b) a leading two-part carriage (20) and a trailing two-part carriage (30) slung to the underside of the platform; (c) a set of wheels or rollers (14, 15, 16, 17) rotatably attached to each of the two-part carriages; and (d) two diagonally-located struts (25, 26) attached to and joining outer, laterally opposing ends (27, 28, 37, 38) of the two-part carriages. Each two-part carriage includes two parallel, laterally-extending suspension members (21, 22, 31, 32).

FIELD OF THE INVENTION

This invention relates to a light transport vehicle which is directlysteerable by a person or persons standing on a platform forming part ofthe vehicle.

BACKGROUND OF THE INVENTION

Skateboards have been in common use since the 1970s. The commonly usedconstruction of a skateboard involves the use of an elongated, flexibleplatform. A leading set and a trailing set of wheels or rollers aresuspended below the platform. Each suspension point uses a laterallydisposed carriage for the set of wheels or rollers, the suspension beingattached to the underside of the platform The carriage is so constructedthat each component of the set of wheels or rollers is separated to asubstantial degree. The carriage is usually referred to as a "truck".

A conventional skateboard is steered by standing on one side or theother of the flexible platform which flexes to one side or the other.This flexion produces tension on the connectors attaching the trucks tothe flexible platform causing the sets of wheels or rollers to turn andhence the skateboard as a whole to turn.

An object of the present invention is to provide a light transportvehicle which uses certain of the operating principles of skateboardsand applies them to a more heavy duty transport vehicle.

It is a further object to provide such a light transport vehicle whichmay be motorised.

It is yet a further object to provide such a light transport vehiclewhich can travel over a considerable variety of terrains.

BRIEF SUMMARY OF THE INVENTION

This invention, therefore, provides a light transport vehicle which isdirectly steerable by a person or persons standing on the vehicle, whichvehicle comprises:

(a) an elongated, flexible platform;

(b) a leading two-part carriage and a trailing two-part carriage slungto the underside of the platform;

(c) a set of wheels or rollers rotatably attached to each of thetwo-part carriages; and

(d) two diagonally-located struts attached to and joining outer,laterally opposing ends of the two-part carriages,

wherein each two-part carriage comprises two parallel,laterally-extending suspension means.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings illustrate one embodiment of the invention in which:

FIG. 1 is an isometric view from the rear right of a light transportvehicle according to the invention;

FIG. 2 is an isometric view from the front right of the vehicle of FIG.1;

FIG. 3 is a plan view from the top of a portion of the suspension andsupport structures forming part of the vehicle;

FIG. 4 is a cross-sectional view along line 4--4 shown in FIG. 3;

FIG. 5 is a cross-sectional view similar to FIG. 4 except that theleading wheel shown in FIG. 4 is replaced by a small ski means, and

FIG. 6 is a cross-sectional view similar to FIG. 5 with the addition ofan extra set of wheels and traction belts.

DETAILED DESCRIPTION OF THE INVENTION

The elongated, flexible platform is preferably a relatively long narrowstructure. It is preferably constructed from a laminated material suchas plywood or a composite material containing carbon or glass fibres.

It is preferred to use a set of wheels, preferably relatively squatpneumatic wheels such as those used for competition vehicles such asgo-karts.

It is possible to replace each member of the leading set of wheels byshort ski means. In addition it is possible to assist the grip of thevehicle on the trailing surface by providing a third set of wheels tothe rear of the vehicle and, if desired, coupling corresponding wheelsof this third set to the trailing set using traction belts which travelover the surface of the travelling surface. This modification issuitable for snow surfaces, for example.

The struts are so constructed from suitable material and are of suitabledimensions so as to be rigid but relatively light. Suitable materialsare steel or carbon fibre-based composites. The struts may be attachedvia flexible attachment means.

Each two-part carriage may comprise two suspension means which arejoined together at one or more regions. Alternatively the two suspensionmeans are integral with the remainder of the twopart carriage.

Preferably each suspension means in a two-part carriage is attached tothe underside of the platform and each suspension means is joined to theother suspension means by bracket means.

Preferably the vehicle is driven by a small motor coupled to the set ofrear wheels by means of gears or a variable belt drive.

Turning to the accompanying drawings, in FIGS. 1 and 2 a light transportvehicle 10 comprises an elongated, flexible platform 11 supported by anundercarriage 12. A motor 13 is mounted on the rear of the undercarriage12 and the whole vehicle is supported on wheels 14, 15, 16 and 17.Wheels 14 and 17 are relatively small front wheels and 15 and 16 arerelatively large rear wheels.

Considering FIGS. 3 and 4, undercarriage 12 comprises a leading two-partcarriage 20 positioned laterally across the underside of the front ofthe platform 11; see FIG. 1. Carriage 20 comprises two parallel,elongate suspension means 21 and 22 joined by a first bracket means 23.First bracket means 23 is mounted on transverse tube 24. Diagonal struts25 and 26 are linked to ends 27 and 28 respectively of suspension means22.

Numeral 30 indicates a trailing two-part carriage and numerals 31 and 32two parallel suspension means similar to suspension means 21 and 22.Suspension means 31 and 32 are joined by second bracket means 33.Carriage 30 is mounted on transverse axle 34.

Carriage 20 is mounted by way of suspension means 21 and 22 upon frontblock 40 which is attached to the forward part of the underside ofplatform 11. Carriage 21 is attached to the underside of first block 40by means of a first nut, bolt and bush means 41 penetrating one wing ofsuspension means 21. Another wing of suspension means 21 extends into aguide 42 also attached to the underside of first block 40. A similararrangement is provided to attach suspension means 22 to first block 40except that, since suspension means 22 is positioned lower thansuspension means 21, a first extension piece 43 is provided betweenfirst block 40 and suspension means 22.

In a similar manner carriage 30 is mounted by way of suspension means 31and 32 upon second block 44. A second extension piece 45 extendsdownwards from second block 44 to provide part of the attachment forcarriage means 30. A second nut, bolt and bush means 46 forms the otherprincipal part of the attachment for carriage means 30.

A sprocket gear 35 is shown near one end of axle 34 and a disc brake 36at the other end of axle 34. Thus motor 13 couples to axle 34 throughgear 35.

Numerals 37 and 38 indicate the points of attachment of struts 26 and 25respectively to suspension means 32.

Turning now to FIG. 5, both front wheels may be replaced by short skimeans--one ski means 50 only is shown. A suspension column 51 joins skimeans 50 to transverse tube 24.

It is possible to provide structure on the platform to assist a personor persons to ride on the vehicle and carry items of equipment, forexample, golf clubs.

It is possible in the case of the ski version to provide a third set ofwheels 100 located to the rear of the trailing set of wheels 15, 16 forthe purpose of providing extra grip. Wheels 100 are mounted by supportbars 102 to axle 34. The extra grip wheels may be coupled to thetrailing set of wheels 15, 16 by means of traction belts.

One purpose of diagonal struts 25 and 26 is to provide greater rigidityto the structure of the vehicle as a whole. In the absence of the strutsplatform 11 would tend to bow to an unacceptable degree. However, theplatform 11 may still flex to some extent to one side or the other andthe wheels of each set of wheels may turn correspondingly as in aconventional skateboard. Furthermore, linking provides four-wheelsteering and stability. This effect is not dependent upon the standingposition(s) adopted by the person(s) on the platform.

The purpose of the two-part carriages 20 and 30 is to provide moreeffective load distribution and transmission than is the case in asimple "truck" used to suspend wheels or rollers in a conventionalskateboard.

In the drawings the trailing set of wheels is illustrated in such amanner that the wheels project above a plane through the upper surfaceof the platform. It is preferred that these wheels do not extend abovethis plane for ease of riding on the platform

I claim:
 1. A skateboard-type light transport vehicle which can beridden by a user and which is directly steerable by weight transfer of aperson or persons standing on the vehicle, which vehicle comprises:(a)an elongated, flexible platform; (b) a leading two-part carriage and atrailing two-part carriage attached to the underside of the platform,each two-part carriage comprising two parallel, laterally extendingsuspension members joined together at at least one region; (c) a firstpair of wheels rotatably attached to the trailing two-part carriage anda second pair of wheels attached to the leading two-part carriage; and(d) two diagonally-located struts attached to and joining outer,laterally opposing ends of the two-part carriages, wherein opposite endsof the struts which are attached to the opposing ends of the two-partcarriage form flexible attachments.
 2. A vehicle as claimed in claim 1,wherein the platform is a long narrow structure having a length and awidth, with the length thereof much greater than the width.
 3. A vehicleas claimed in claim 2, wherein the platform is constructed fromlaminated material.
 4. A vehicle as claimed in claim 1, wherein thewheels are squat pneumatic wheels.
 5. A vehicle as claimed in claim 1,wherein the suspension members forming part of each two-part carriageare integral with a remainder of the carriage.
 6. A vehicle as claimedin claim 5, wherein each suspension member in each two-part carriage isattached to the underside of the platform, and further comprisingbracket means for joining each suspension member to the other suspensionmember.
 7. A vehicle as claimed in claim 1 wherein each suspensionmember in each two-part carriage is attached to the underside of theplatform, and further comprising bracket means for joining eachsuspension member to the other suspension member.
 8. A vehicle asclaimed in claim 1, wherein a small motor is coupled to the first pairof wheels attached to the trailing two-part carriage, by means of agear.
 9. A vehicle as claimed in claim 1, further comprising:a rear axlemounted to the trailing two-part carriage, with the first pair of wheelsmounted on the rear axle; a motor mounted to the trailing two-partcarriage; and a drive connection for drivingly coupling the motor to therear axle to rotate the first pair of wheels.
 10. A vehicle as claimedin claim 1, wherein the two suspension members of each carriage areseparately and independently secured to said platform at differentpositions.
 11. A skateboard-type light transport vehicle which can beridden by a user and which is directly steerable by weight transfer of aperson or persons standing on the vehicle, which vehicle comprises:(a)an elongated, flexible platform; (b) a leading two-part carriage and atrailing two-part carriage attached to the underside of the platform,each two-part carriage comprising two parallel, laterally extendingsuspension members joined together at at least one region, wherein thetwo suspension members of each carriage are separately and independentlysecured to said platform at different positions, and wherein onesuspension member of each carriage is positioned lower than the othersuspension member of the respective carriage; (c) a pair of wheelsrotatably attached to the trailing two-part carriage; (d) ski membersattached to the leading two-part carriage; and (e) twodiagonally-located struts attached to and joining outer, laterallyopposing ends of the two-part carriages.
 12. A vehicle as claimed inclaim 11, wherein gripping of a travelling surface is assisted by anextra rear pair of wheels.
 13. A vehicle as claimed in claim 12, whereinat least one traction belt extends around the wheels attached to thetrailing two-part carriage and the extra rear pair of wheels.
 14. Avehicle as claimed in claim 11, further comprising:a rear axle mountedto the trailing two-part carriage, with the pair of wheels mounted onthe rear axle; a motor mounted to the trailing two-part carriage; and adrive connection for drivingly coupling the motor to the rear axle torotate the pair of wheels.
 15. A skateboard-type light transport vehiclewhich can be ridden by a user and which is directly steerable by weighttransfer of a person or persons standing on the vehicle, which vehiclecomprises:(a) an elongated, flexible platform; (b) a leading two-partcarriage and a trailing two-part carriage attached to the underside ofthe platform, each two-part carriage comprising two parallel, laterallyextending suspension members joined together at at least one region,wherein the two suspension members of each carriage are separately andindependently secured to said platform at different positions, andwherein one suspension member of each carriage is positioned lower thanthe other suspension member of the respective carriage; (c) a first pairof wheels rotatably attached to the trailing two-part carriage and asecond pair of wheels attached to the leading two-part carriage; and (d)two diagonally-located struts attached to and joining outer, laterallyopposing ends of the two-part carriages.